As a novel functional material with excellent performances, cerium oxide (CeO2) plays a key role in emerging technologies, environments and energy issues, such as the removal of nitrogen oxides in automobile exhaust; moreover, the high oxygen vacancy mobility and ion conductivity of the cerium oxide are utilized to produce electrodes of solid oxide fuel cells, and the unique electronic structure of the cerium oxide is utilized in the cosmetics industry and the glass manufacturing industry to absorb ultraviolet lights, and produce optical collection devices and optical displays, etc. The electrode electromotive force between Ce3+/Ce4+ is lower, while the CeO2 material is a semi-open fluorite crystal structure, so CeO2 can release O2 when being under an oxygen-deficient external environment and absorb O2 when being under an oxygen-enriched environment under the premise of keeping its crystal structure stable. Since the CeO2 material has the ability to store and release oxygen, oxygen species in a gas phase can be transferred to a solid surface through the “respiration effect” of CeO2 during a heterogeneous catalysis process, thus promoting the catalysis process. Therefore, it is of great value to study catalytic materials based on cerium oxide. Moreover, Hassanzadeh-Tabrizi et al from Tarbiat Modares University of Iran prepared an Al2O3—CeO2 composite material by sintering in 2011. Researches show that compared with single Al2O3, the addition of CeO2 suppresses the growth of Al2O3 crystal grains, and increases 28% fracture toughness and 17% flexural strength, which shows that CeO2 also has preferable application prospect in the aspect of improving the mechanical property of Al2O3 (Journal of the American Ceramic Society, 2011, 94(10), P3488-3493).
A method of dispersing CeO2 nanoparticles on ceramic supports is considered to be a method for effectively improving the oxygen capacity of CeO2, and increasing the sintering properties and the mechanical properties of the ceramic composite material. Common dispersion methods include: ball milling, impregnation, and sol-gel, which are time consuming and often result in poor dispersion effect or production of toxic liquid wastes. In 2014, Pournajaf et al from Islamic Azad University of Iran synthesized Al2O3—CeO2 nano composite material powder by a reverse microemulsion method which adjusts the size and shape of the powder by changing the surface activities of sodium dodecyl sulfate, hexadecyltrimethylammonium bromide and polyoxyethylene dodecyl ether, but may also result in the problems of time-consuming and environmental pollution. On the other hand, the effects of a precursor and a solution for the synthesis of CeO2 are very complicated; therefore, the repeatability is very poor (Ceramics International, 2014, 40(3), P4933-4937). A chemical vapor deposition method is a relatively novel way to disperse the nanoparticles on the supports, which ensures sufficient contact between the powder and reaction gases in a rotating CVD furnace, so as to obtain evenly dispersed nanoparticles. Compared with general wet chemical method, the advantage of the chemical vapor deposition method is that no solution is used; therefore, an after-treatment process and an environmental pollution problem are avoided. The important influence factors of the chemical vapor deposition method include a precursor feeding rate, an oxygen feeding rate, a rotating speed, or the like, and the capacity and particle sizes are adjusted through the above-mentioned conditions.